Connect the strobe to pin2 and the data to any other pin. Then arrange for an interrupt to be generated on the falling edge of the strobe line. In the interrupt service routine look at the data line and save it into a byte acting as a shift register. Page 3 of that data sheet tells you exactly what to do.For interrupt information see:-http://www.arduino.cc/playground/Code/Interrupts

Hello, i just received the head, and here is the specification of the datasheet. can someone give me a help?

For backwards compatibility, the ASIC powers up in Old Mode by default. A reset must be initiated to enter New Mode. To initiate a reset, take STROBE high if not already high, then force DATA low, and then take STROBE low again. After initiating the reset, while still holding DATA forced low, take STROBE high and then low again before releasing DATA. Then once again take STROBE high then low to complete the reset sequence. At the end of this sequence the ASIC will be in the very low-power "OFF" state. To arm the ASIC to read cards, one more sequence of taking STROBE high and then low is required.

STROBE is a Schmitt-triggered digital input to the ASIC. It is mainly used to extract data from the ASIC as described below. From the Armed-to-Read state, once three flux transitions have been detected, the ASIC signals "Card-Present" by pulling DATA low. It then begins to store data from the card into its buffer. The controller should respond to the Card-Present indication by taking STROBE high. The ASIC will respond to this rising edge of STROBE by taking DATA high, clearing the Card-Present indication. The controller should then take STROBE low and wait for DATA to fall, indicating the Buffer-Ready state. This falling edge of DATA is the signal to a micro-controller that the card swipe has ended, and the on-chip memory of the ASIC contains data to be read. The data is extracted or read from the buffer memory by pulsing STROBE input high and then low to advance the data pointer that steers the data to the DATA pin. During data extraction and when the STROBE input is low, a low on DATA represents a "one" bit and a high represents a "zero" bit. DATA returns to its default high state after each rising edge of the controller-issued STROBE. Note that after DATA initially falls to its Buffer-Ready state, the ASIC will ignore further card signals until reset.